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#ifndef SPACES_REEDS_SHEPP_STATE_SPACE_
#define SPACES_REEDS_SHEPP_STATE_SPACE_

#include <boost/math/constants/constants.hpp>
#include <cassert>

typedef int (*ReedsSheppPathSamplingCallback)(double q[3], void* user_data);
typedef int (*ReedsSheppPathTypeCallback)(int t, void* user_data);

class ReedsSheppStateSpace
{
public:
  /** \brief The Reeds-Shepp path segment types */
  enum ReedsSheppPathSegmentType
  {
    RS_NOP = 0,
    RS_LEFT = 1,
    RS_STRAIGHT = 2,
    RS_RIGHT = 3
  };

  /** \brief Reeds-Shepp path types */
  static const ReedsSheppPathSegmentType reedsSheppPathType[18][5];

  /** \brief Complete description of a ReedsShepp path */
  class ReedsSheppPath
  {
  public:
    ReedsSheppPath(const ReedsSheppPathSegmentType* type = reedsSheppPathType[0],
                   double t = std::numeric_limits<double>::max(), double u = 0., double v = 0., double w = 0.,
                   double x = 0.);

    double length() const
    {
      return totalLength_;
    }

    /** Path segment types */
    const ReedsSheppPathSegmentType* type_;
    /** Path segment lengths */
    double length_[5];
    /** Total length */
    double totalLength_;
  };

  ReedsSheppStateSpace(double turningRadius) : rho_(turningRadius)
  {
  }

  double distance(double q0[3], double q1[3]);

  void type(double q0[3], double q1[3], ReedsSheppPathTypeCallback cb, void* user_data);

  void sample(double q0[3], double q1[3], double step_size, ReedsSheppPathSamplingCallback cb, void* user_data);

  /** \brief Return the shortest Reeds-Shepp path from SE(2) state state1 to SE(2) state state2 */
  ReedsSheppPath reedsShepp(double q0[3], double q1[3]);

protected:
  void interpolate(double q0[3], ReedsSheppPath& path, double seg, double q[3]);

  /** \brief Turning radius */
  double rho_;
};

#endif